Stock-Based Compensation - Stock Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 61,837	$ 39,453	$ 170,155	$ 114,827
Income tax benefit	(10,562)	(6,593)	(29,062)	(19,188)
Stock-based compensation expense after taxes	51,275	32,860	141,093	95,639
Cost of products
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	6,478	4,493	18,174	12,684
Cost of maintenance and service
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	1,959	1,694	6,109	4,675
Research and development expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	31,367	19,383	86,469	55,802
Sales and marketing expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	10,863	7,360	29,483	21,790
General and administrative expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense before taxes	$ 11,170	$ 6,523	$ 29,920	$ 19,876